Question 1

Which statement is correct for a motor unit?

Accepted Answer

A)  a single motor neuron plus all of the muscle fibres it innervates 
B)  a single muscle fibre plus all of the motor neurons that innervate i. 
C)  all of the motor neurons supplying a single muscle 
D)  a pair of antagonistic muscles 
A)  a single motor neuron plus all of the muscle fibres it innervates 
B)  a single muscle fibre plus all of the motor neurons that innervate i. 
C)  all of the motor neurons supplying a single muscle 
D)  a pair of antagonistic muscles

Question 2

Muscle tension does not develop in isometric contractions.

Accepted Answer

A) True 
 B)False

Question 3

The ____________________ is a modified endoplasmic reticulum within muscle.

Accepted Answer

sarcoplasm

Question 4

Indicate which of the characteristics in question applies to each of the muscle fibre types by using the answer code (options may be used more than once or not at all).
-contains considerable myoglobin

Accepted Answer

A) slow-oxidative fibre 
B) fast-oxidative fibre 
C) fast-glycolytic fibre 
A) slow-oxidative fibre 
B) fast-oxidative fibre 
C) fast-glycolytic fibre

Question 5

The heart initiates its own action potentials without any external influence.

Accepted Answer

A) True 
 B)False

Question 6

Atrophy can develop in a muscle by either denervation or disuse.

Accepted Answer

A) True 
 B)False

Question 7

What directly blocks cross bridge interaction between actin and myosin in skeletal muscle?

Accepted Answer

A)  acetylcholine 
B)  Z lines 
C)  calcium 
D)  tropomyosin 
A)  acetylcholine 
B)  Z lines 
C)  calcium 
D)  tropomyosin

Question 8

Skeletal muscle fibres are formed during embryonic development by the fusion of many smaller cells.

Accepted Answer

A) True 
 B)False

Question 9

Myosin has ATPase activity.

Accepted Answer

A) True 
 B)False

Question 10

Which statement concerning the H zone is correct?

Accepted Answer

A)  It is the area within the middle of the Z lines where the thin filaments do not reach. 
B)  It shortens or disappears during contraction. 
C)  It contains only thin filaments. 
D)  It is the area within the middle of the I band. 
A)  It is the area within the middle of the Z lines where the thin filaments do not reach. 
B)  It shortens or disappears during contraction. 
C)  It contains only thin filaments. 
D)  It is the area within the middle of the I band.

Question 11

Indicate which bands are being described in each statement by writing the appropriate letter(s) in the blank by using the answer code (options may be used more than once or not at all).
-composed of thin filaments only

Accepted Answer

A) A band 
B) I band 
C) H zone 
A) A band 
B) I band 
C) H zone

Question 12

Cross bridges have actin binding sites that are normally covered by troponin and tropomyosin except during excitation-contraction coupling.

Accepted Answer

A) True 
 B)False

Question 13

Which statement concerning cross bridges is correct?

Accepted Answer

A)  They extend between the A and I bands and bend to pull the bands together during muscle contraction. 
B)  They are formed by the spherical actin molecules. 
C)  They extend from the thick filaments and bind to actin, then bend to pull the thin filaments in closer together during muscle contraction. 
D)  The A band is shorter. 
A)  They extend between the A and I bands and bend to pull the bands together during muscle contraction. 
B)  They are formed by the spherical actin molecules. 
C)  They extend from the thick filaments and bind to actin, then bend to pull the thin filaments in closer together during muscle contraction. 
D)  The A band is shorter.

Question 14

What is the smallest unit of contraction within a skeletal muscle?

Accepted Answer

A)  myofibril 
B)  muscle fibre 
C)  sarcomere 
D)  thin filament 
A)  myofibril 
B)  muscle fibre 
C)  sarcomere 
D)  thin filament

Question 15

What happens during contraction of skeletal muscle fibres?

Accepted Answer

A)  Contractile proteins contract. 
B)  Thin filaments slide inward toward the A band's centre as a result of cycles of cross-bridge binding and bending. 
C)  Thick and thin filaments become tightly coiled, thus shortening the sarcomere. 
D)  I bands slide in between the A bands. 
A)  Contractile proteins contract. 
B)  Thin filaments slide inward toward the A band's centre as a result of cycles of cross-bridge binding and bending. 
C)  Thick and thin filaments become tightly coiled, thus shortening the sarcomere. 
D)  I bands slide in between the A bands.

Question 16

Indicate which type of muscle is associated with the property in question by using the answer code (options may be used more than once or not at all).
-contains gap junctions

Accepted Answer

A) skeletal muscle only 
B) single-unit smooth muscle only 
C) cardiac muscle only 
D) skeletal muscle and cardiac muscle 
E) skeletal muscle and single-unit smooth muscle
F)single-unit smooth muscle and cardiac muscle
G)skeletal, single-unit smooth, and cardiac muscles 
A) skeletal muscle only 
B) single-unit smooth muscle only 
C) cardiac muscle only 
D) skeletal muscle and cardiac muscle 
E) skeletal muscle and single-unit smooth muscle
F)single-unit smooth muscle and cardiac muscle
G)skeletal, single-unit smooth, and cardiac muscles

Question 17

In an isotonic contraction,only 25 percent of the energy consumed is realized as external work and the remaining 75 percent is converted to heat.

Accepted Answer

A) True 
 B)False

Question 18

Which statement concerning foot proteins is correct?

Accepted Answer

A)  They span the gap between a lateral sac of the sarcoplasmic reticulum and the cell membrane. 
B)  They are believed to serve as Ca2+ channels. 
C)  They project from the thick filaments, bind to the thin filaments, and subsequently bend to pull the thin filaments inward toward the A band's centre during muscle contraction. 
D)  Each foot protein contains two subunits arranged in a specific pattern. 
A)  They span the gap between a lateral sac of the sarcoplasmic reticulum and the cell membrane. 
B)  They are believed to serve as Ca2+ channels. 
C)  They project from the thick filaments, bind to the thin filaments, and subsequently bend to pull the thin filaments inward toward the A band's centre during muscle contraction. 
D)  Each foot protein contains two subunits arranged in a specific pattern.

Question 19

Slow-oxidative muscle fibres would be found in high density in the leg muscles of Olympic sprinters.

Accepted Answer

A) True 
 B)False

Question 20

Describe calcium's role in the contraction of the sarcomere in skeletal and cardiac muscle tissues.

Accepted Answer

Calcium plays a crucial role in the cont

Which statement is correct for a motor unit?

Muscle tension does not develop in isometric contractions.

The ____________________ is a modified endoplasmic reticulum within muscle.

Indicate which of the characteristics in question applies to each of the muscle fibre types by using the answer code (options may be used more than once or not at all). -contains considerable myoglobin

The heart initiates its own action potentials without any external influence.

Atrophy can develop in a muscle by either denervation or disuse.

What directly blocks cross bridge interaction between actin and myosin in skeletal muscle?

Skeletal muscle fibres are formed during embryonic development by the fusion of many smaller cells.

Myosin has ATPase activity.

Which statement concerning the H zone is correct?

Indicate which bands are being described in each statement by writing the appropriate letter(s) in the blank by using the answer code (options may be used more than once or not at all). -composed of thin filaments only

Cross bridges have actin binding sites that are normally covered by troponin and tropomyosin except during excitation-contraction coupling.

Which statement concerning cross bridges is correct?

What is the smallest unit of contraction within a skeletal muscle?

What happens during contraction of skeletal muscle fibres?

Indicate which type of muscle is associated with the property in question by using the answer code (options may be used more than once or not at all). -contains gap junctions

In an isotonic contraction,only 25 percent of the energy consumed is realized as external work and the remaining 75 percent is converted to heat.

Which statement concerning foot proteins is correct?

Slow-oxidative muscle fibres would be found in high density in the leg muscles of Olympic sprinters.

Describe calcium's role in the contraction of the sarcomere in skeletal and cardiac muscle tissues.

The Foundation of Physiology

Cell Physiology

The Central Nervous System

The Peripheral Nervous System

Principals of Endocrinology; The Central Endocrine Glands

Cardiac Physiology

Vascular Physiology

The Blood

Body Defences

The Respiratory System

The Urinary System

Fluid and Acid Base Balance

The Digestive System

Energy Balance and Temperature Regulation

The Endocrine Glands

The Reproductive System

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Exam 6: Muscle Physiology

Which statement is correct for a motor unit?

Muscle tension does not develop in isometric contractions.

The ____________________ is a modified endoplasmic reticulum within muscle.

Indicate which of the characteristics in question applies to each of the muscle fibre types by using the answer code (options may be used more than once or not at all). -contains considerable myoglobin

The heart initiates its own action potentials without any external influence.

Atrophy can develop in a muscle by either denervation or disuse.

What directly blocks cross bridge interaction between actin and myosin in skeletal muscle?

Skeletal muscle fibres are formed during embryonic development by the fusion of many smaller cells.

Myosin has ATPase activity.

Which statement concerning the H zone is correct?

Indicate which bands are being described in each statement by writing the appropriate letter(s) in the blank by using the answer code (options may be used more than once or not at all). -composed of thin filaments only

Cross bridges have actin binding sites that are normally covered by troponin and tropomyosin except during excitation-contraction coupling.

Which statement concerning cross bridges is correct?

What is the smallest unit of contraction within a skeletal muscle?

What happens during contraction of skeletal muscle fibres?

Indicate which type of muscle is associated with the property in question by using the answer code (options may be used more than once or not at all). -contains gap junctions

In an isotonic contraction,only 25 percent of the energy consumed is realized as external work and the remaining 75 percent is converted to heat.

Which statement concerning foot proteins is correct?

Slow-oxidative muscle fibres would be found in high density in the leg muscles of Olympic sprinters.

Describe calcium's role in the contraction of the sarcomere in skeletal and cardiac muscle tissues.

The Foundation of Physiology

Cell Physiology

The Central Nervous System

The Peripheral Nervous System

Principals of Endocrinology; The Central Endocrine Glands

Cardiac Physiology

Vascular Physiology

The Blood

Body Defences

The Respiratory System

The Urinary System

Fluid and Acid Base Balance

The Digestive System

Energy Balance and Temperature Regulation

The Endocrine Glands

The Reproductive System

Filters